The present invention is an improvement related to the carton with core retainers disclosed in U.S. Pat. No. 4,298,123, owned by the assignee of the present invention.
The '123 patent is directed to overcoming the tendency of an entire product roll to come out of the box when a portion of the product on the roll is being dispensed. Core retainers, projections integrally formed with the carton and the overlapping ends walls thereof, are located at each end of the box to project inside the core after the carton is erected and filled. The projecting retainers are designed to resist the rolled product's tendency to be pulled or removed entirely from the carton as force is applied to the product to remove a portion thereof from the carton.
The '123 patent is also directed to a carton blank for forming a carton having core retainers therein comprising top, bottom, front and back side panels integrally formed with and hingedly attached to each other, an inner wall having an orifice and hingedly connected to each end of one of said side panels, an overlapping wall having a projection and hingedly connected to each end of a second one of said side panels, and an outer wall connected to each end of a third one of said side panels, whereby when the blank is folded and erected with the product on a hollow core contained therein, the inner wall, overlapping wall and outer wall on each end are folded into overlying relation to form a composite end wall of the carton with the projections retaining the core in place in the carton.
Although the '123 patent represents a significant improvement in packaging for rolled products, there are some problems that patent does not address. One such problem relates to economics of production and, specifically, to the need for a package that minimizes the expenses in manufacturing and erecting a carton having retainers for retaining rolled products. Cartons such as the '123 carton are relatively expensive to make because they require numerous and complex die-cuts and removal of portions of at least two flaps used in each end wall of the carton.
A related problem not addressed by the core retainers disclosed in the '123 patent, nor those suggested in U.S. Pat. No. 4,813,539, is that the inward folding or deflection of the tabs or members forming the core retaining projections can pose manufacturing difficulties, because it must be accomplished within relatively strict tolerances. If the projections are deflected or folded inwardly too far, they or the carton may be torn or will fail to engage to perform their function.
Other issues that have been unsatisfactorily unaddressed in the art are the need for optimizing locking performance of the projections or tabs forming the core retainers and the need for a simpler projection engagement mechanism whereby there is a reduced risk that the carton and core retainer structure will be torn during erection, filling and shipping of the carton containing the product. Additionally, it is desirable to reduce the amount of paperboard used for fabricating a carton, just as, in the interest of economy, the number of machining steps for preparing the carton blank should be reduced. Simply put, with current core retaining packages, efficiency, performance and durability are not enhanced to an optimum degree.
Accordingly, there is a need for a simple, strong, efficient, disposable paperboard package with core retainers for containing and dispensing roll-type materials.